Cutting head for cleaning sewer pipes



Oct. 2, 1956 c. cHmsToDoLu 2,765,149

CUTTING HEAD FOR CLEANING SEWER PIPES Filed April l5, 1954 il; Z6

i nited This invention relates to devices for cleaning sewer and drain pipes, and has particular reference to a cutting head and carrier which are especially suitable for removing roots, leaves, and other obstructions which accumulate in drain and sewer pipes.

In some residential communities, considerable damage occurs to the drain and sewer pipes when the roots of adjacent trees and bushes grow into them. Various devices are now known to the public for cleaning drains and sewers, all of which have met with doubtful success when encountering the roots of 4certain trees.

It is, therefore, an object of this invention to provide a cutting head which is constructed and arranged so that it will cut through any obstruction which might be encountered in a drain or sewer pipe regardless of how tough and fibrous the lobstruction may be.

Another object of the invention is to provide a device of the character indicated, which is constructed and arranged so that it will readily work in and travel through a U trap and operate beyond such trap with the same eciency as it would in a straight pipe.

Another object of the invention is to provide a cutting head which is constructed with a pair of comparatively thick cutting blades, which are provided with convexly shaped back faces and concavely shaped front faces, there being a continuous cutting edge running along the outside edges of said blades, which cutting edge reverses its direction near the -center line of said head.

Another object of the invention is to provide a cutting head which is constructed with a pair of forwardly directed axially parallel blades, which are comparatively thick at their bases and which taper from the bases to a sharp cutting edge, which continues .along the outer edges of both blades, and reverses its direction near the center line of the head.

Another object of the invention is to provide a cutting head of the character indicated, which is provided with special means for attaching it to a exible cable.

Another object of the invention is to provide a cutting head of the character indicated, which has a cylindrical body portion whose length is less than its diameter, there being a deep central bore in said body for receiving a exible shaft, whereby the head may be directed around sharp curves, and through a U trap of a drain.

Another object of the invention is to provide a cutter head which is of such size, shape and arrangement that it will eiiiciently function inside a drain or sewer pipe, to cut closely to the inside walls of the pipe, to remove therefrom all manner of obstruction.

The foregoing and other objects and advantages of the invention will become more apparent as the description proceeds, reference being made from time to time to the accompanying drawings forming part of the within disclosure, in which drawings:

Fig. 1 is a perspective view of the device embodying the invention, with parts broken away.

Fig. 2 is a section taken through a portion of a wall atent O ice and oor, and illustrating the manner in which the device embodying the invention may be utilized in a U trap and in the drain beyond.

Fig. 3 is an enlarged elevational view of the device shown in Fig. 1, with parts broken away, and in section, to illustrate the relation of the parts.

Fig. 4 is a section taken substantially on the line 4 4 of Fig. 3.

Fig. 5 is a section taken substantially on the line S-S of Fig. 3.

Fig. 6 is a section taken substantially on the line 6 6 of Fig. 3.

Referring now more particularly to the drawings, it will be understood that in the embodiment herein disclosed, the reference character 7 indicates a flexible shaft, to the end of which is secured the cutter head embodying the invention. The cutter head consists of a body portion S, the length of which is somewhat smaller than the diameter. The body 8 is preferably formed with rounded edges 9, so that it may readily be withdrawn from a rain pipe after it has been used. The body S has a central bore 10 for receiving the end of a flexible shaft 7, and the device is secured to the flexible shaft 7 by means'of a plurality of allen screws 11, which are adapted to be received in the threaded radial bores 12. The head 8 is provided with a key-way 13, which is arranged to receive the end 14 of the heavy wire, which forms the flexible shaft 7.

lt will be noted that the end 14 of the flexible shaft 7 engages the key-way 13 ahead of the set screw 11A, which is directed into the key-way 13. The set screw 11A serves as a stop, or locking means, to prevent the shaft 7 from being withdrawn from the head 8 when the device is being used. This is particularly important, in that it prevents the head from being dislodged from the flexible shaft 7, as the device is being retrieved from the inside of a pipe, after the cutting operation has been finished. lt also prevents the flexible shaft 7 from being pulled from the head 8 in the event that all of the set screws 11 should become loose as a result of vibration.

The head 8 is provided at its forward end with a pair of blades 1S and 16, which blades may be formed integrally with the head S, or may be made separately of a harder tool steel, and secured to the head 8 by means of welding, as at 17. The axes of the blades 15 and 16 are substantially parallel with the axis of the head 8. The blades 15 and 16 are comparatively thick at the base, as shown in Fig. 5, .and they taper forwardly and outwardly, to a continuous, sharp, cutting edge 18, 19 and 20, which continuous cutting edge reverses its direction at 19, as shown in Fig. 4. The surface 21 of the blade 15 and the surface 22 of the blade 16 are convex, and the surface 23 of the blade 15 and the surface 24 of the blade 16 are concave, as shown in Figs. 4 and 5. The continuous and reverse-direction cutting edge 1S, 19 and 20, and the convex and concave surfaces 21, 22, 23, and 24 provide the blades with a peculiar ability to cut the roots, or any other obstruction in the drain pipe, cleanly and closely to the inside walls of the pipe.

Other tools now known to the public, intended for cleaning roots and the like from drains, will simply bore a hole through the roots or obstructions at the approximate center of the pipe. On the other hand, the instant cutter head will rotate on its longitudinal axis and at the same time, because of its weight, balance, and peculiar and critical shape, and because the flexible shaft 7 is mounted deeply into the head, the head will move in a wider circle defined by the inside walls of the pipe and will cleanly cut and remove from the walls any obstruction within the pipe.

The instant cutting head 8, because of its comparatively short length, in contrast to its diameter, will readily negotiate a trap 25 (Fig. 2), which is shown in relation toa wall 26 and floor 27, and a drain pipe 2S, from which it is desired to remove roots 29 or any other obstruction. The instant euttinghead S not only may Vbe extended through a Conventional U trap, but it will operate efciently within a drain pipe a considerable distance beyond the U trap.

The convexly shaped back faces 21 and 22 of the blades provide clearance for the cutting blades, 'and obviate any tendency of the blades to drag because of friction on the inside walls of the pipe. The convex surfaces also maintain the cutting edges of the Vblades a sufficient distance from the inner walls of the pipe, so that the cuttingedges` cannot be damaged by striking the walls, yet permit the blades to cut roots or other obstructions comparatively close to the inner walls of the'pipe. The side curvature ofthe blades also helps the device to ride over certain fixed obstructions which might be encountered in Ythe pipes.

It will be noted Vthat the device is constructed so .that there is a continuouscutting action along the entire edge 18, 19 and iii, and as the head is .advanced toward the roots or other obstructions, the leading edges of the blades will start to cut lirst, which cutting action is effected both along the outside edges 18 and 2.0Y and along the inside edges which center at 19. This arrangement of the cutting edges causes a substantial pu-lverization of the obstruction, instead of causing a hole to be drilled through the center thereof as is the case with conventional tools.

The cutter head and the flexible shaft may be rotated by several conventional means (not shown) which are well known to the public, and which form no part of this invention. Y

It is believed that the operation of the device is obvious from the foregoing description.

Having described my invention, what I claim and desire to secure by Letters Patentv is:

1. A cutting head for cleaning sewer pipes comprising a rounded-body having a width greater than its length, and having a deep axial bore including means to receive and secure a flexible shaft therein, and a pair of short forwardly extending blades integral with said body, said blades having one continuous reverse curve sharp cutting edge, extending along their front and sides.

2. The structure of claim 1, in Which said blades have concavely formed front faces and convexly formed back faces, and said cutting edge reverses its direction near the axis of said head, the said cutting edge lying .in dierenty planes when considered from the front to the rear ,of said blades.

3. The `structure ofclaim 1, in which said continuous cutting edge defines an undulating path along the outside edges of said blades.

4. rEhe structure of claim 1, in which said continuous cutting edge denes an undulating path along the outside edges of said blades, and reverses its direction at a point along an extension oftheV axis of said body.

5. The structure of claim' 1, in which the cutting `edges of said blades deiine a substantially V shaped open area at the front of said head.

6. The structure of claim l, inwhich said blades are comparatively thick at the base and taper to a thin cutting edge, which continues along the outside of both, blades, and reverses itself at a point `along the axis of the head.

References Cited in the file of this patent UNlTED STATES yPATENTS 400,939 Newman Apr. 9, 1889 1,401,353" Murray Dec. 27, 1921 1,427,019 Putnam Aug. 22, 1922 1,591,625 Holder Juiy 6, 1926 1,601,855 Davis Oct. 5, 1926 1,963,561 Sanger June 19, 1934 2,255,800 Miller Sept. 16, 1941 2,628,380 Therrien Feb. 17, 1953 2,675,570 Sacks Apr. 20, 1954 

